I just read a post that stated an 89 L98 was dyno'd at 186HP and 277TQ (with minor upgrade mods).

It was my understanding that the stock 89 L98 was 245HP and 345TQ.

Even if you subtract for drivetrain loss (auto tranny, etc), isn't 186/277 low? No offense intended, but I own an 89 L98 and it was my impression that it produced more power/tq stock than that.

Any info would be appreciated.
Thank you.

 

You're right, but that is at the crank. 186/277 at the wheels isn't too bad, think about how old these motors are...they often lose quite a bit of power after years of abuse and neglect.

 

That was RWHP & RWTQ on the dyno, the numbers you have are for the Fywheel. Also each L98 is going to be different on the dyno.
Now if you tested your it may be higher or lower, nothing is exact.

 

I guess I expected the RWHP to be higher. I guess-timated that with a "typical" drivetrain loss (I used 14%), a stock L98 should still have around 211RWHP (245-34). However, I am not a mechanic or mathematician Maybe 14% isn't enough?

So I'm assuming that would imply that a stock LT1 (rated at 275FWHP) would have about 225 (or so) RWHP?

Sorry if I am confusing things... I've never had my car dyno'd and I'm just trying to figure it all out.

 

An 89 L98 would only put out 230 hp with single cat and 240 with dual cats. Not a big difference from 245.

I think that the loss in power through the drivetrain is usually around 15-20 % depending on your transmission.

 

In 1989 the TPI with MAF 350 was rated at 235 horsepower and 330 ft lbs of torque. This was with the dual cat option. If you did not have the dual cat option the power was 225 HP and 325 ft lbs of torque. I have the Pontiac brochure for 1989 and got the specs out of it. By the way I bought my GTA new in 1989 and have had it ever since.

Now in 1990 the power went up again with the speed density system to the 245 Horsepower rating. Allen

 

Sorry, I forgot to mention that my transmission is the stock TH700R4 auto and my car does have dual cats.

 

The tech data section at the main page has all the HP and TQ specs for all the different years and engines.

 

Another problem is you are running #24 injectors with a stock prom. You are most likely running way rich causing low power. Get a chip with the injector constant set for the 24s.

 

Note: Drivetrain Loss for RWHP & RWTQ with a automatic 700R4 will be between 20/22% and not the 14%you used (way to low).

15/18% is the number for a manual.

 

Thanks for the clarification, DJP87Z28 (and everyone else)!

87350IROC, how do I get a chip setup specifically for 24# injectors? I know everyone (or atleast most people) in the forums dislike Hypertech and/or Jet chips, but would either of these be better for my 24# injectors than the stock chip I am currently running?

Thanks again.

 

I know the off the shelf chip won't compensate for the bigger chips, they are meant for stock applications only. I don't have prom burning skills myself, so i don't know how to do it, but an injector constant has to be changed in the chip.